Stovepipe casing



M. R. SHPLEY STOVEPIPE CASING Filed 0G13. 22, 1924 Dec. 3, 1929.

wa/'c Patented Dec. 3, 1929 UNITED STATES MARION R. SHIPLEY, OF MANHATTAN BEACH, CALIFORNIA STOVEPIPE CASING Application. led October 22, 1924. Serial No. 745,117.

This invention relates to the oil well industry, and it relates particularly to stovepipe casing utilized therein.

As an oil well is drilled, a. well casing is advanced into the hole for reinforcing the wall against cave-ins, excluding ground water and for other purposes. Two types of casing may be used for this purpose, screw casing and stovepipe casing. Screw casing is made up from sheet wrought iron which is rolled into circular form and welded. Each end of the casing is provided with screw threads which are arranged to be screwed into couplings or other members for securing them together. Stovepipe casing of the present type comprises inner and outer layers of comparatively soft sheet metal which are rolled into circular form and secured together either by riveting, by welding or by rolling inter-engaging corrugations in the two layers after they are placed together. In other words, it is general practice to form stovepipe casing by staggering the sections relative to each other so that the abutting ends of the sections of the inner member are offset relatively to the abutting ends of the outer member, these two members being secured together in any of the above mentioned manners in order to form the stovepipe casing in a continuous piece. i

One of the great disadvantages found in using either screw casing or the present stovepipe casing is that neither of these casings will withstand substantially any frictional wear. This is due to the fact that they are both ^madeof a comparatively soft material. The stovepipe casing must be made of a comi paratively soft material because of the necessity of securing the inner and outer layers together, and this securing necessitates the punching, welding, riveting or forming of corrugations in both of the layers of this type of stovepipe casing. When drilling in hard `strata suoli `as rock, the drill progresses very slowly.` -If the hole is outof alignment or the drill pipe `is bowed, tool joints of the string of drill pipe will engage with the well easing at various points. This produces a considerable wear at one place and both screw casing and the present stovepipe casing wear i vention.

through very readily, owing to the softness of the material which the manufacturers are compelled to use as is previously explained. The wearing through of the casing causes the string of well casing to separate which is obviously detrimental. In the present stovepipe casing it is found `that the casing will separate even when only the inner layer thereof is worn through. This is due to the fact that the forming of the stovepipe in a continnous length depends upon the cooperation between the inner and outer layers thereof. When the inner layer is worn through, it fails to perform its function and the casing will separate or cause leakage.

It is an object of this invention to provide a stovepipe casing which will possess a tensile strength equivalent to that of any of the present casings, but in addition to which will possess frictional resisting j qualities j which enormously exceed that of any of the present type of casings whether it be screw casing or stovepipe casing. I am able to accomplish this due to the novel construction of my in- The stovepipe casing of my invention consists of inner and outer layers of material. The outer layer of the casing is formed of soft steel or a fairly ductile material which is of such a character that it may be readily formed in such a manner as to provide joints therein necessary for securing portions thereof together to form acontinuous member. The outside layer is solely for the purpose of providing the tensile strength necessary for the casing. The inner layer of my stovepipe casing comprises a tubular shaped member which is placed inside the outer layer and which has absolutely no joints of any character, and which is in no way attached to the outer layer. Owing to this, it is possible for me to make the inside layer of my casing of a material which is of an extremely hard character. In practice the material from which I form the inner inember is of a hardness which is substantially per cent greater than that used in any other casing of which I have knowledge. The outer member of my invention is arranged to take all of the tensile strains which may be placed on a casing, and the vinner member is arranged to receive all of the friction which may be placed on a casing. It is not probable that the inner layer will be Worn through due to friction because of its great hardness and great resistance to frictionalwear. If, however, this inner member should be wornthrough, the casing will not separa-te because of the fact vvtha'tthe inner layer in no way cooperatesv with the outer layer to providethecasing in continuous form.

It is another object of the invention to provide oint fora casingof this character which willvnot leak. 1 It is also an object ofthe invention topro- ,videa stovepiipe casingwhich will havegieat ril'al S t ren'gth'.` HI accomplish thisobj ect by `pr tividingA fthe, Outer layer 'in very short lengths jvv'liicli.'k are' ljoined tog'e'therhby fluidtight joints ofiny invention. These joints `being of sucha character as to p'rovide'gi'eat `-radial strengthare situated fairl'yvclose together aiidftherefore provide a stovepipe casighaving agreat radial strength.

j' y25 A Itis another object-'of the invention to provide Aa stovepipe easing of this character which'iseasy'to install, economical to yprovide `and superior toother stovepipe casings in the above mentioned respect.

( kOther objects and t-lie'fespeciall advantages lof lthis invention will be made evident hereinafter.

Referring to they drawings which are for lillustrative'purposes only, f 55 vFig. ljisavertical sectional view through a Vstovepipe ('iasi'ngV presenting the features of my invention. l

Fig. ,2 is a view showing the joint structure i provided by my invention, this view showing the members in'position ready to be secured together.

Fig. 2, but being shown secured together.'

` r. Y Fig. is ahoriz'ontal section taken as indicated'by the line/1444 of Fig. 3.

YVith reference to the drawings, I provide anouter tubular member 11 which is made up of vsections 12, these sections 12-being made M `from sheet nietall possessing sufficient ducmntility to' permit forming of jointsfor secur ing'thesese'ctions together. I provide a joint for securing Asections 12' together, as shown yclea'rly'in Figsp2, 3 and 4. With particular efiternallip 14which is'provided lby bending ftheiend of the' section backonitself, as clearly y shown Fig. 3. On theiipper end 'of each of the sections 12 I provide a bell portion 15.

mi the end of whicliis provided with an internal retaining 16. TheV internal diameter yof the bell portion 1 5 ifsofsuchsize as to be of the same diameter lasgthe external face of the lip 14 on thelower'end of' each member 12. The bell-r portion l'is'provided with an open Vthe adjacent outer tubular sections 12, the

sections are first disposed as shown in Fig. 2. The bell portion 15 is then expanded as indicated by the dotted lines 23 of this figure in any suitable manner, such as by driving a wedge into the open seam 1S. It will be seen that this eipanding is necessary to permit -tli`e"`pa`sjsing of the lip v14 into the interior vof Ithe bell portion 15 past the inter'nalretainingflip 16 thereof.v After the lip 14 has been inserted, as shown in lFig/3, the bell portion 15"'ii'iay be 4allowed toreturn to its normal position. 'A suitable clamp, notshown, may then be utilized for contracting the bell portion l15 around the lowerend of the upper section 12 and the "open se'a1n'18 'thereof welded, as indicated at 25in Fig.4. Owing to the fact that the external diameter of the 'packii'ig 21 is 'slightly larger than the external diameter 14 of the upper member, the packing `member will be compressed when the bell portion 15 is constricted there'around,

Iand provides 'a flu'idtightsealvbetween the sections. I j

The inner tubular lmember 3Qis comprised of sections 31, these sections being made up lof vlengths of 'verv' hard sheet steel rolledinto 'ftubular forni. vThese lengths may be welded together as indicated lat'32 to form the sections -31.

As shown in Fig. 1, a 'section 31 of the inner tubular member 3Q is inserted into the lower Fig. Y3fisfasectioii offthe joint shown in stalled, this section 37 telescop'ing inside ythe outer section 35, the upper` end thereof projecting a sliortdistance above the upper end of the section 35, the lower end thereof abutting with the upper end of the section 31 as j `indicated at 38. After this, another outer .W reference to Fig. 2, the lower end of eachof "#Vthefsections 1 2'is provided with an annular tubular ,section 39 is joined with the section i 35, after which another inner tubular section may .be .inst'alled. vIt'will be seen that this fprocedure'may be continuously carried'ut as the stovepipe casing is assembled.

I have merely ab'utted "thefends of these lengths together inside the outer'member and have then galvanized the assembly.

In practice, the outer sections 11iand 12 are iso ` of a length of about five feet. This means that there is a joint every live feet in the casing. The joint is of such a character, as is obvious from the drawings, that it will be much stronger than the tensile strength of a single layer. At the oint the layers are bent in such a manner as to be doubled and should, therefore, provide a strength which should approach nearly twice that of a single thickness of material. By placing these joints very close together, l am able to provide a casing which has very high radial resisting strength. Sections such as l1 and l2 are assembled together in lengths of 25 to 30 feet at the shop. When the casing is installed in a well, these lengths are in turn secured together by similar joints. This practice eliminates considerable work at the well and increases the economy of the casing and convenience for the installation thereof.

From the foregoing description, it will be seen that a stovepipe casing of this character is very economical to provide and may be very readily installed, owing to the fact that the cost of material and the cost of making is comparatively small, and that the joints of the outer tubular member 11 may be very easily and quickly made. The joints provided in the outer tubular member are absolutely impervious to fluid providing a reliable and permanent seal between the sections l2. My casing has high radial compressive resistance as well as considerable axial strength. The outer member being made of a ductile material permits the forming of the joints and the providing of the outer tubular member in continuous form so as to provide the necessary tensile strength for the Casino. The inner member is made of hard steel plates, this being permitted due to the unique construction previously explained, these steel plates being of a hardness which exceeds that of any material used at the present time in casings.

From the foregoing description, it will be seen that my invention is based almost entirely upon the use of an outer member which supplies tensile strength, and an inner member which supplies high frictional resisting qualities, these members being very independent of each other as a matter of function. The outside layer or member provided by my invention provides a continuous member which is equivalent to the other casings,

screw type or stovepipe, as regarding tensile strength. By the utilization of the inner member which may be considered as a liner for the outer member, the casing provided by my invention is possessed of frictional resisting qualities which very greatly exceeds that of any casing known in this art. F or this reason I consider stovepipe casing of my invention greatly superior to any other casing on the market at the present time.

I claim as my invention:

l. A joint for stovepipe` casing comprising: a first member having its end portion bent back along and in close contact with the outer surface of its body portion to form an annular exterior lip; a second member hav-' ing a belled portion formed at the end thereof into which said end of said first member extends, and having its end portion bent back along and in close contact with the inner surface of its body portion to form an internal retaining lip; and a packing member disposed between the adjacent faces of said annular lip of said first member and said retaining lip of said second member.

2. A stovepipe casing coupling comprising: two casing sections, an end of one extending within an end of the other to provide an annular inter-tubular space; annular elements disposed in said space, one of said elements being provided upon each of said sections, said elements being axially opposed to cach other to prevent the parting of said coupling; and a tubular lining disposed tightly within said sections and supporting the end of said inner casing section of said coupling against a tendency of said end to collapse inwardly.

3. A stovepipe casing coupling comprising: two casing sections an end of one extending within an end of the other to provide an annular inter-tubular space; annular elements disposed in said space, one of said elements being provided upon each of said sections, said elements being axially opposed to each other to prevent the parting of said coupling; a tubular lining disposed tightly within said sections and supporting the end t of said inner casing section of said coupling against a tendency of said end to collapse inwardly; and an annular packing member disposed in said inter-tubular space between said annular elements.

4. A'joint for stovepipe casing comprising: a first member having its end portion bent back along and in close contact with the outer surface of its body portion to forni an annular exterior lip; and a second member havingl a belled portion formed at the end thereof and into which said. end of said first member extends, and having its end portion bent back along and in close Contact with the inner surface of its body portion to form an internal retaining lip.

5. A stovepipe casing coupling adapted to withstand abnormal tension stresses, and coinprising: two casing sections, an end of one extending inside an end of the other to provide an annular inter-tubular space; opposing elements disposed in said space and supported against crushing by the portions of said sections which bound said space, one of said elements being secured to each of said sections so as to loclr said sections against axial separation and means disposed within the end of said inside veasing"section to 'ventithe collapsing of said end.

y y6. 'A tjoint for-stovepipe casing -comprising: 'a primary tubular member; a locking element oiitwardly'and reVerselybent from an i end ltliereof secondary tubular menipreber having'a belled portion formed at an i' end thereof; a lockingelement inwardly and reversely bent from 'said eiidof said secondary member, -said end ofv said primary inem* beribei'ng disposed in saidlbel-led lportion so that 'said looking elements inter-loclrand a i tubular insert isnugly fitting within -said pri- 'mary and secondarymembers and resisting ar tendency of `said primary member tocollapse inwardly. A

.7. A method'of joining two secondary section end upon said primary sec- 30v tion end; and welding opposite edges of said secondary section split to retain said sections locked together by opposition of said locking Y elements.

'8. A method of joining two sections in the formation of stovepipe casing, said method comprising: forming an outwardly .extending rigid looking element on an end of a primary' section; forming an end of a secondary sect-ionY so that it is belled and split; forming an inwardly extending rigid locking element upon said end of said secondary section so that this will pass over said outwardly extending locking element; projecting said end of said primary section into said vbell-ed and split end of said secondary seetion; contracting said secondary section end upon said primary section end; 'and ]oining opposite edges of .said secondary section split to retaiii'said sec-tions locked together by opposition of said locking elements.

9. A method of joining two sections of vtubing of substantially equal and uniform diameter which consists in forming an outwardly vextending rigid flange upon a male end of one of said sections by outward and reverse bending of the metal thereof, forming an inwardly extending rigid flange upon Va. female end of the other section by an inward and reverse'bending of the metal thereof, expanding the metal of said female end into a split bell rse that said'inale iange may V,be received therein past said vfemale aiige,

contracting said bell about said male end so 'that said'iiiale flange and said-femae flange K y Sections in the formation "of stovepipe casing, said method' comprising: forming'an outwardly extending interlock, and securing thespl-it edges of said bell together.

In testimony whereof, I have hereunto'set my hand at Los Angeles, California, thislth day of October, -192/1.

`MARION R. SHIPLEY. 

